Derrick pedestal



April 23, 1940. D. s. FINE ET AL 2,198,281

DERRI CK PEDESTAL Filed June 28. 193B g W PIES.

1740970575: Dav/0 .5. F/NE m/ Patented Apr. 23, 1940 PATENT ,oFFieE DERRICK PEDESTAL David S. Fine, New York, and Harold D.

Mount Vernon, Y.

Hussey, 7

Application June 28, 1938, Serial No. 216,360

4 Claims.

This invention relates to derrick constructions, and particularly to improved means tending to prevent the overturning of the pedestal thereof and to means adjustable to various angular positions with respect to one another, connecting the derrick sills with the pedestal. Further characteristics of the invention relate to constructional features and to the interrelation of parts which individually and conjointly function as hereinafter more fully described, illustrated and claimed.

For a detailed disclosure of the invention, reference is to be made to the accompanying drawing, the following specification and the appended claims.

In the drawing:

Figure l is a side elevation of a derrick embodying, our invention;

Figure 2 is an enlarged view illustrating the improved means for connecting the pedestal with the derrick sills;

Figure 3 is an enlarged plan of the pedestal, showing sills adjustable relative thereto;

Figure e is a section on line IV-.IV of Figure 3;

Figure 5 is a detail plan of a connector adapted to be secured to a sill and adjustably interlocked with the pedestal;

Figure 6 is a side elevation thereof;

Figure 7 is a skeleton diagram illustrative of the present invention; and

Figure 8 is a similar diagram, contrasting the conventional practice with the present invention as exemplified in Figure 7.

Referring in detail to the drawing, the numeral I0 represents a conventional derrick mast having a boom H pivotably secured thereto at I2. The boom is adapted to carry any suitable live load, indicated at L in Figure 1, secured by any conventional form of lifting tackle, including, for example, a cable C reeved through conventional sheaves c, c and 0 The boom is actuated by conventional means, including a cable reeved through sheaves s, s and s substantially as shown.

The mast l 0, at its lower end, is provided with a ball-like member I3 which is seated on a socketed bearing ring l4 carried in a recess of a pedestal 16. This pedestal has a base I! adapted to be seated on any suitable foundation, indicated at l8.

Heretofore it has been customary in derrick design to provide sill members which serve to take the reaction received from the derrick boom in a more or less horizontal direction and such sill members have been so located, with respect to the location to which the mast is seated on the pedestal, as to have a tendency to overturn the pedestal. It is a particular feature of this invention to so arrange and coordinate the parts that the tendency to overturn the pedestal will be effectively overcome. We secure this desirable advantage over constructions heretofore proposed by providing an arrangement such as best shown in Figures 2 and 4 of the drawing, wherein the plane of the connection between the sills l9-ill and the pedestal substantially or approximately coincides with the zone where the base portion 13 of the mast reacts against the pedestal bears 4- Comparison of Figures '7 and 8 diagrammatically contrast the arrangement of the present invention with the old conventional practice. With particular reference to these figures, in which Figure '7 shows the invention and Figure 8 shows the old practice, the vertical line or represents the center line of the mast, line 0y represents the center line of the boom, and the line 02 represents the center line of one of the sill members l9. In accordance with our invention, the sill center line oz is substantially or approximately coincident with a horizontal plane cutting the center of the region where the rounded end of the mast contacts the bearing ring. As so arranged, the lateral or substantially horizontal component of the force of the boom is so trans-' mitted that it reacts directly along the substantially horizontal center lines oz of the respective sills. In other words, the center line of each sill is substantially or approximately coincident with the center of the region where the mast is seated on the pedestal bearing. As so arranged, the tendency of the kick of the mast to overturn the pedestal is overcome by eliminating a moment arm through which said kick acted according to prior practice.

Figure 8 conventionally illustrates the old prior practice wherein 0' represents the region where the mast was seated on the pedestal, and z'm represents the horizontal center line of the sills. Thus, in such old practice, the vertical distance o'-m constituted a moment arm indicated by the dimension M through which the kick or lateral thrust of the boom transmitted a force of appreciable magnitude which had an objectionable tendency to overturn the pedestal. By our invention the moment arm M is eliminated; the design of the derrick pedestal is simplified and the calculation of stresses in the parts are correspondingly simplified. The net result of such improvements effects significant economies in the design and construction of the derrick and 'makes possible the production of a pedestal of as good or better strength characteristics than those heretofore used with the same or less metal than heretofore required.

The sills which receive the lateral component of the thrust or kick from the boom heretofore have frequently been located in fixed, predetermined, angular relationship. In many cases, this caused inconvenience in setting up a derrick in proper position to adequately resist the thrust, and frequently required a special design of derrick pedestal to suit the peculiar exigencies to meet working conditions presented in different projects. To overcome such inherent disadvantages in the prior type of derricks, we have constructed the derrick of our present invention in such manner that the angular relationship between the sills can be readily varied to meet requirements. To this end we have provided a means for efiecting a sliding connection between the sill members and the pedestal whereby the angular relationship between such sill members can be readily varied to meet the requirements for the particular job for which the derrick is to be set up. Such an adjustable connecting means between the sills l9 and the pedestal is best shown in Figures 3 to 6, inclusive, wherein it will be seen that the sill is provided with undercut, angular, grooved portions til-2! forming guides for" coaction with the ribs 22-23 formed on the sill conhector members 2d24. As s0 arranged the sills may be said to be interlocked with the pedestal in, such a manner as to make an angularly adjustable connection. therewith. The connector members', in the embodiment illustrated, are of bifurcated form, each having arms 2525 between which ends of the sills are accommodated and connected by means of pins 26. As thus arranged, the. angular relationship between two or more sills it can be readily varied by merely sliding either one or both of the sill connectors in the undercut, grooved portions of the pedestal. The pedestal is provided with a cut-away portion 2! for the initial engagement of the connecting members 2424 with the annular interlocking slotted portion thereof.

While we have described quite specifically the embodiment of the invention herein illustrated, it is to be understood that the drawings and detailed description are to be construed in'an illustrative rather than a limiting sense, and that the appended claims are to be interpreted as broadly as is consistent with the prior state of the art.

We claim: I

1. A derrick comprising a mast, a boom, a pedestal having a bearing for rotatably supporting the mast, a pair of sills connected to the pedestal, the projected center lines of said mast and sills converging toward a common locus within the pedestal bearing, said pedestal having an annular undercut grooved seat formed therein and said sills carrying a member slidably interlocked with said undercut grooves so as to provide for angular adjustment of the sills relative to one another.

2. A derrick comprising a pedestal, a mast pivotally seated on a bearing portion thereof, a loadsupporting boom pivotally secured to the mast,

said pedestal having an annular seat with undercut grooves formed therein, connecting members having ribs adjustably engaging said undercut grooves and sills coasting with the connecting members to receive thethrust transmitted to the pedestal by the boom.

3. A derrick comprising a pedestal, a mast piv- Otally seated on a bearing portion thereof, a. loadsupporting boom pivotally secured to the mast, said pedestal having an annular undercut grooved seat formed therein at substantially or approximately the same elevation as the mast-bearing portion, and sills having means slidably interlocked with said annular seat for directly receiving the lateral thrust from said boom.

i. A derrick comprising a pedestal having a mast-bearing and an annular grooved portion surrounding the bearing, a mast seated on the bearing, a boom pivotally secured to the mast, sill members for taking the lateral thrust of the boom and connectors secured to said sill members and making an interlocking connection with said grooved portion.

DAVID S. FINE.

HAROLD D. HUSSEY. 

